3

The term....:
"upper respiratory infection" usually refers to the common cold, but generally means any infection that effects the upper part of the respiratory (breathing) system, namely the nose and throat. The lower respiratory tract is made up of the large airways and the lungs. A lower respiratory infection usually means bronchitis or pneumonia, tends to be more severe and to affect breathing much more.
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4

Yes:
Certain viruses are the common causes of lower respiratory tract infection: respiratory syncytial virus, influenza, parainfluenza, adenovirus, and human metapneumovirus, also with some attention to rhinoviruses and some new viruses (human coronaviruses and bocavirus).
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5

Lower respiratory:
Upper respiratory infections involve upper airways such as throat, nasal cavity, paranasal sinuses, eustachian tubes, trachea as, nd bronchi. When the disease process in the bronchi, or bronchitis, continues, it could begin to involve lower airways in the lung tissues, which is then more advanced lower respiratory infections or pneumonia.
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6

Axillary temperature:
Axillary temperature is 1.5 to 2 degrees lower than body temperature, so 99.1 is actually 100.6 to 101.1. Body temperature vaires during an infection depending on the body's response to fight the infection.
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7

Different causes:
The upper respiratory tract (nose, throat, upper airways) are usually infected by viruses. While annoying, these viruses can be cleared by our immune systems without much problem. The lower respiratory tract (bronchioles and air sacs of the lung) are more susceptible to more serious bacterial infections. These often require antibiotics to clear the infection.
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9

Needs of the system:
The blood pressure needs to be just high enough to push the blood around through the vessels & supply the needs of the body.Babies have shorter & narrower pipes to push the blood through so the pressure can be lower.Babies have a faster metabolism than adults, & the higher heart & respiratory rates that add the oxygen (at low pressure) to help them grow.
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